The free trial of Window Washer is fully functional, so it can do everything the full version can, but is limited to 30 days of use. That said, what it does is use a DoD or Gutman wipe process, in which the files are overwritten several times, making the data virtually unrecoverable...for the most part the data is gone for good.
However, data recovery specialists can still recover the data using specially-designed devices that can extract the original 1s and 0s. This is why major corporations and government agencies wipe the drive, degauss them, and then grind them up into pieces.
In short, Window Washer is good enough 99% of the time, but if you're worried about the FBI, NSA, etc finding traces on your hard drive then you might want to step it up a notch and physically destroy the drive...it's the only way.
Hope this helps,
John
P.S. Don't forget that your Internet Service Provider, and your IT department if this is at work, also keep logs on what communications occur, so wiping the drive only solves the local issue...there is still a log off-site that is not under your control.
Does the free windows washer download from webroot completely clear any internet activity prior to that so that forensic computer digging is pointless?
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